Internally illuminated signs are customarily required by fire and building codes of various governmental agencies to identify an exit or a direction to an exit. An acceptable construction of such an internally illuminated sign is one wherein the letters for the word "EXIT" are cut in a stencil and a directional indicating arrow opening is cut into the stencil at each end of the word "EXIT". When the manufacturer of the sign ships the sign, the sign is shipped with solid arrow covers in the respective arrow openings in the stencil so that no direction is indicated. Upon selection of the location for mounting the sign, one of the arrow covers may be removed from an opening so that the arrow opening is illuminated, thereby indicating direction. This general type of construction is well known. An example of such a construction is shown in U.S. Pat. No. 5,247,756, entitled, "Sign Apparatus With Insertable Directional Arrow" issued Sep. 28, 1993, to Robert M. Johnstone.
The Johnstone disclosure teaches the use of arrows mounted in openings in a stencil, wherein the arrows are held in position by a snap action. The snap action requires a fabrication wherein close tolerances must be maintained so that the arrows may be readily removed and inserted relative to the supporting stencil.